The present invention relates to a network system composed of a plurality of electronic equipments which are interconnected to one another through logical paths so as to construct a complex electronic musical instrument or other electronic compositions. More specifically, the invention relates to a self-constructable and reconstructable network system which can automatically restore the logical paths once the same has been programmed.
In a recent audio/video (AV) system, a plurality of audio and video equipments or components are interconnected to build up a complex AV installation. For example, a typical AV system is composed of a television set, a video tape recorder, an audio component, a karaoke machine and so on. Their input terminals and output terminals are mutually connected to each other to set up the AV system. In such a case, all members of the system are physically connected together one by one by means of a coaxial cable, a shield cable, a parallel line cable and so on.
Specifically, referring to FIG. 22, the complex electronic musical instrument is composed of several electronic musical components or units which are connected to each other through a Musical Instrument Digital Interface (MIDI), which is designed according to an international standard. In the system of FIG. 22, a keyboard 101 has a MIDI output terminal OUT connected to a MIDI input terminal of a sequencer (SEQ) 102 through a line L101. The sequencer 102 has a MIDI output terminal OUT connected to a MIDI input terminal IN of a first tone generator 104 through a line L102. The first tone generator 104 has a MIDI intermediate terminal THRU connected to a MIDI input terminal IN of a second tone generator 105 through a line L103. The second tone generator 105 has a MIDI intermediate terminal THRU connected to a MIDI input terminal IN of a third tone generator 106 through a line L104. Further, the first, second and third tone generators 104, 105 and 106 have respective output terminals AUDIO-OUTs which feed output signals to an input terminal AUDIO-IN of a mixer 103 through separate lines L105, L106 and L107. The mixer 103 produces a musical tone signal from its output terminal AUDIO-OUT. The MIDI intermediate terminal THRU provided in the first and second tone generators operates to directly output or pass an input signal received at a preceding input terminal, as it is.
In the conventional structure of FIG. 22, the plurality of the electronic components are physically interconnected by a number of cables which would require a considerable installation space. Further, once the cable lines are disconnected, it would require a laborious re-coupling work to reconstruct the same complex system. Further, in the conventional structure, the member components are serially connected to each other by the MIDI lines because a MIDI message is transferred in the form of a serial data. Such a rather redundant arrangement of the MIDI lines would share a considerable installation space. If one MIDI line is inadvertently disconnected from a circuit loop, a signal cannot be transferred to succeeding members so that the musical system may stop tone generation. Even worse, it would require a laborious repairing work to recover the disconnected line.